Comparison of parasitic infections and body condition in rufous mouse lemurs (Microcebus rufus) at Ranomafana National Park, southeast Madagascar

Body condition may be an important indicator for many infectious diseases and parasites, and may ultimately affect an individual’s fitness. Although some research has correlated body condition and parasite loads in other nonhuman primates, little information has been investigated in prosimian primates. In this study we compare parasitic infections and body condition in a member of the Cheirogaleidae family (Microcebus rufus: rufous mouse lemur) at Ranomafana National Park, southeast Madagascar. This species is characterized by seasonal fattening in preparation for the dry season followed by torpor, and it is important to understand the fluctuation between parasites and infections according to seasonal body condition. We trapped 72 individuals of the species inside Ranomafana National Park (RNP) after the dry season. These individuals were brought to the Centre Valbio Laboratory (CVB) and were subcutaneously micro-chipped with subdermal transponders for permanent identification. We recorded morphometric data, body condition, species richness and prevalence of ectoparasites and gastrointestinal parasites. We found that individuals that had both high number of parasite species as well as high prevalence of ectoparasites and gastrointestinal parasites had better body condition. There is some indication that being in good condition is important in controlling infections.Peer reviewe

Smelling fit: scent marking exposes parasitic infection status in the banded mongoose

Preference for uninfected mates is presumed beneficial as it minimizes one’s risk of contracting an infection and infecting one’s offspring. In avian systems, visual ornaments are often used to indicate parasite burdens and facilitate mate choice. However, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where experimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. Here, we investigate the interplay between parasite load (estimated using fecal egg counts) and scent marking behavior in a wild population of banded mongooses Mungos mungo. Focusing on a costly protozoan parasite of the genus Isospora and the nematode worm Toxocara, we first show that banded mongooses that engage in frequent, intensive scent marking have lower Isospora loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high Isospora and Toxocara loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals